急性冷、热应激对肉鸡肝脏和心脏组织中HSPs表达的影响

将45只28日龄罗斯308肉鸡随机均分为三组进行急性应激处理:热应激组在急性热应激下持续饲养6 h(温度为39℃,湿度为90%);冷应激组在急性冷应激刺激下持续饲养6 h(温度为11℃,湿度为90%);对照组鸡群在正常饲养条件下饲养(温度为26℃,湿度为60%)。采用实时荧光定量PCR(q RT-PCR)分别对肝脏和心脏组织中的4种热应激蛋白基因(HSP60、HSP70、HSP90、HSP110)的表达量进行对比分析。结果表明:在心脏组织中,HSP60表达量在冷、热应激下均无显著变化(P0.05);HSP90表达在冷应激下显著下降(P0.05);HSP70表达在冷、热应激下均显著上升(P0.05、P0.01);HSP110表达在冷应激下无显著变化,在热应激下极显著上升(P0.01)。在肝脏组织中,HSP60在冷应激下表达量显著下降(P0.05),热应激下表达无显著变化(P0.05);HSP70和HSP110在热应激条件下表达量极显著上升(P0.01);HSP90表达量在冷、热应激下均无显著变化(P0.05)。结果揭示:急性热应激相比于急性冷应激对应激蛋白的表达影响更显著;在急性热应激条件下,心脏和肝脏组织中HSP70和HSP110表达量均极显著上升。     

热应激雏鸡免疫器官中热休克蛋白70的定位研究

通过检测热休克蛋白70（heat shock protein,HSP70）在免疫器官及细胞上的分布规律,研究热应激雏鸡免疫器官中热休克蛋白70的定位及表达。结果显示：HSP70在常温饲养雏鸡的胸腺、脾脏、法氏囊中均有明显的表达,在胸腺、脾脏的细胞中主要以胞浆表达为主,而法氏囊中则以胞核表达为主,脾脏中HSP70的表达强度最为稳定。热应激时,胸腺中HSP70的IOD值随日龄增长而逐渐降低,末期显著低于对照组（P〈0．05）;脾脏中HSP70的IOD值随日龄增长逐渐降低,末期稍低于对照组（P〉0．05）;法氏囊中HSP70的IOD值与饲养日龄间无明显规律,末期高于对照组（P〉0．05）。结果表明,热应激对雏鸡胸腺的损伤明显,胸腺细胞通过自身合成HSP70抵抗热应激的能力较差,而对脾脏和法氏囊影响较小。     

热应激对淮南麻鸭血清生化指标及肝脏与心脏HSP70 mRNA表达的影响

试验旨在探讨热应激对淮南麻鸭血清生化指标及肝脏与心脏热休克蛋白HSP70 mRNA表达的影响。将60只40日龄雌性淮南麻鸭随机分成6组,每组10只,分别为对照组及热应激2、4、6、8、10 h处理组,将试鸭于(20±1)℃温度下适应性饲养7 d,于第8天开始,对照组仍置于(20±1)℃温度下,试验组迅速升温至(40±1)℃并分别施以2、4、6、8、10 h的热应激处理,试验结束后试鸭全部屠宰取样进行血清生化指标测定和检测肝脏、心脏组织热应激蛋白HSP70 mRNA表达水平。结果表明:热应激显著降低淮南麻鸭血清总蛋白、白蛋白和球蛋白浓度(P0.05),遵循二次曲线回归模式;血清谷丙转氨酶随着热应激处理时间的增加显著升高(P0.05),并表现出显著的线性趋势;肌酸激酶和谷草转氨酶活性随着热应激处理时间的增加显著升高(P0.05),遵循二次曲线回归模式;肝脏与心脏HSP70 m RNA表达水平呈先升高后降低的趋势,并分别于6 h和4 h后达到峰值。以上表明,在一定的热应激强度范围内,淮南麻鸭通过调节机体的代谢及HSP70表达量来响应热应激的影响。     

热休克蛋白70在热应激鸡原代心肌细胞中的表达与定位

为研究热应激后鸡原代心肌细胞中热休克蛋白70(HSP70)的表达量及其定位的变化,试验将体外培养的鸡原代心肌细胞分为6组,其中1组作为对照(未进行热应激处理),其余5组于42℃热应激处理0.5,1,2,4,8 h,Western-blot检测HSP70在6组鸡原代心肌细胞中的相对表达量,间接免疫荧光法测定热应激处理1 h后HSP70在鸡原代心肌细胞中的定位。结果表明:热应激后HSP70在鸡原代心肌细胞中的表达量呈先上升后下降趋势;与对照相比,热应激8 h后鸡原代心肌细胞的HSP70表达量显著降低(P0.05);HSP70在对照与热应激1小时时的心肌细胞中均有表达,且在细胞浆与细胞核中均有分布,但主要分布于细胞浆中。说明热应激对HSP70在鸡原代细胞中的表达产生影响,但对其在细胞中的分布无明显影响。     

急性热应激鹅心和肝和肺及肾脏组织中HSP70 mRNA及蛋白的表达

选取1日龄健康雁鹅60只,随机分为6组,单笼饲养于环控仓内。6周龄时,A组置于(22±1)℃作为对照,B、C、D、E、F组分别施于2、4、6、8 h和10 h(40±1)℃的急性热应激处理,处理后立即剖杀,取心、肝、肺和肾脏组织,实时荧光定量PCR测定HSP70 mRNA表达量,免疫组织化学方法测定HSP70表达量。结果表明:急性热应激处理可显著提高各组织中HSP70 mRNA及HSP70蛋白的表达水平,但不同组织出现显著变化的时间以及随热应激时间延长的变化规律存在差异。心脏组织HSP70 mRNA和蛋白表达量均在热应激2 h后出现显著升高(P0.05),热应激4 h后达到最高值,8 h后降至对照组水平,遵循二次曲线回归模式;肝脏热应激4~10 h间HSP70及其mRNA均显著高于对照组(P0.05),但未表现出显著的线性与二次回归趋势;肺脏HSP70 mRNA表达水平在热应激2~10 h间显著高于对照组(P0.05),HSP70则从热应激4 h起才显著升高,但二者随热应激时间延长均呈显著的线性升高规律;与肺相似,肾脏HSP70及其mRNA表达量随热应激时间的变化趋势也遵循线性回归模式,两者均在热应激4~10 h显著升高(P0.05)。     

急性冷应激对阿勒泰羊HSP60、HSP70和HSP90基因mRNA表达的影响

为研究急性冷应激通过影响热休克蛋白含量的变化对阿勒泰羊抗寒性能、生产性能及抗病性能等的影响,试验设置常温组(15℃±2℃)与冷应激组(-25℃±2℃),每组各5只羊,屠宰后分别采集急性冷应激组(冷应激24 h后)和常温组的心脏、肝脏、脾脏和肾脏组织。采用实时荧光定量PCR技术对HSP60、HSP70和HSP90 mRNA含量变化进行检测,并对HSP60、HSP70和HSP90基因进行同源性分析。结果显示,HSP70和HSP90基因与已有绵羊序列同源性高于99%,而HSP60基因与已有波斯金牛序列同源性高于99%;冷刺激后HSP60基因在心脏、肝脏、脾脏和肾脏组织中的表达较常温组均升高,且在肾脏中的表达量差异极显著(P0.01);冷刺激后HSP70基因在心脏、肝脏、脾脏和肾脏组织中的表达较常温组均升高,且在肝脏和肾脏组织中的表达量差异极显著(P0.01);冷刺激后HSP90基因在心脏、肝脏、脾脏和肾脏组织中的表达较常温组均升高,且在肝脏组织中表达量差异显著(P0.05),而在脾脏和肾脏组织中的表达量差异极显著(P0.01)。表明急性冷应激极大程度地刺激了机体的产热机能,通过通路中的产热相关基因的相互调节使其能量代谢发生改变,从而提高细胞生存率,增强机体对环境胁迫的耐受力,能更好地适应环境温度的变化。试验结果为进一步深入研究急性冷应激对阿勒泰羊机体的影响提供一定理论依据。     

中药复方应激康对热应激肉鸡HSP70m RNA表达影响的研究

为了研究复方中药对热应激肉鸡肝脏HSP70mRNA表达的调控效果;试验选取120只18日龄AA+肉仔鸡,随机分为4组,即复方中药组、维生素组、纯中药组和高温对照组进行试验,试验后每组迅速宰杀3只试验鸡,取肝脏组织进行HSP70mRNA表达的检测。结果表明:高温应激后,复方中药冲剂组和纯中药冲剂组鸡肝脏中HSP70 mRNA表达显著增加,分别比高温对照组、维生素组高2.98倍、3.28倍和4.66倍、5.13倍,说明本试验复方中药可通过上调HSP70 mRNA表达,提高机体热耐受水平,达到保护细胞作用。     

热应激绍兴鸭不同组织HSP70基因mRNA表达研究

研究蛋鸭热应激条件下不同组织中热休克蛋白70(HSP70)基因mRNA表达规律,为揭示蛋鸭热应激反应机理提供参考。60只绍兴蛋鸭25℃饲养20d,其中30只进行40℃热应激处理1h,采取荧光定量PCR方法分别测定不同组织中HSP70mRNA的表达水平。试验组与对照组相比,肝脏、脾脏和胰腺组织HSP70mRNA表达差异不显著,其他6种组织HSP70基因表达量均有不同程度的增加,试验组心脏、腿肌、垂体、下丘脑、胸肌、肾脏中HSP70基因表达量分别高于对照组3.6倍、2.8倍、2.7倍、2.4倍、2.2倍和1.57倍。     

GABA对热应激雏鸡法氏囊组织中IL-IL-6、TNF-TNF-α和HSPHSP70 mRNA表达的影响

试验旨在研究γ-氨基丁酸(GABA)对1~6周龄热应激雏鸡法氏囊组织中IL-6、TNF-α、HSP70 mRNA表达的影响。选择体重相近的1日龄雄性文昌鸡108只,随机平均分为对照组(CK)、热应激(HS)组、GABA+热应激(GABA+HS)组,饲养6周。每周龄末剖取法氏囊组织,采用RT-PCR方法检测雏鸡法氏囊组织中IL-6、TNF-α、HSP70 mRNA的表达水平,分析其在1~6周龄不同组雏鸡法氏囊组织中表达的变化。结果显示:与CK组比较,HS组和GABA+HS组雏鸡法氏囊组织中IL-6 mRNA表达水平上升,且GABA+HS组法氏囊组织中IL-6 mRNA普遍低于HS组;三组的TNF-α mRNA在1~3周龄时均有较低的表达水平,在4~6周龄时表达升高;1~6周龄HS组和GABA+HS组雏鸡法氏囊组织HSP70 mRNA表达水平整体普遍低于CK组。结果表明:热应激导致雏鸡法氏囊组织中IL-6和TNF-α mRNA的表达水平上升,同时抑制HSP70 mRNA的表达,而GABA在一定程度上能够缓解热应激造成的损伤。     

HSP27在热应激致岭南黄鸡雏鸡免疫器官损伤中的作用

为了从热休克蛋白27(HSP27)基因角度揭示热应激致雏鸡免疫器官形态损伤的机制,试验将120只8日龄岭南黄鸡随机分为对照组和热应激组,并构建雏鸡热应激模型,采用组织切片和透射电镜方法对比分析其免疫器官在热应激条件下的显微结构和超微结构变化,并用Real-time PCR方法检测HSP27基因在免疫器官中mRNA的表达差异。结果表明:同日龄阶段比较,热应激组免疫器官发育不良,胸腺细胞数量减少,Hassall氏小体严重退化,胸腺细胞凋亡及坏死数量增多,染色质发生聚集,细胞器肿胀变性;脾脏组织疏松,脾小结生发中心不明显,动脉周围淋巴鞘变薄,淋巴细胞结构疏松,胞核内异染色质减少,线粒体数量增多、结构异常;法氏囊中淋巴滤泡数量减少,皮质和髓质分界模糊,淋巴细胞染色质聚集,胞浆中粗面内质网上核糖体脱落,线粒体肿胀空泡化。法氏囊中HSP27 mRNA相对表达量逐渐降低,在热应激第21天时相对表达量显著高于第28,35天;脾脏中HSP27 mRNA相对表达量逐渐升高,在第35天时相对表达量显著高于第21,28天;胸腺中HSP27mRNA相对表达量与日龄无明显关联,在第28天时相对表达量最低且显著低于第21天和第35天。说明热应激会造成岭南黄鸡雏鸡免疫器官损伤,而HSP27在这一过程中扮演着重要角色。     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein     

Avian brood parasitism — a growing research area in behavioral ecology (part Ⅱ)

正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -